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|
module Expect_test_config = struct
include Expect_test_config
let upon_unreleasable_issue = `Warning_for_collector_testing
end
let get_a_trace () =
let rec loop n =
if n < 0
then Printexc.get_callstack 10, 0
else (
let x, y = loop (n - 1) in
x, y + 1)
in
let trace, _ = loop 10 in
trace
;;
let print_slot trace n =
match Printexc.backtrace_slots trace with
| None -> assert false
| Some slots ->
let slot = slots.(n) in
(match Printexc.Slot.format 0 slot with
| None -> assert false
| Some str -> print_endline str)
;;
let%expect_test (_ [@tags "no-js"]) =
(* We create a backtrace with 10 identical slots and then only print the 5th slot.
Otherwise flambda and non-flambda compilers create slightly different
backtraces. *)
let trace = get_a_trace () in
print_slot trace 5;
[%expect
{|
(* expect_test_collector: This test expectation appears to contain a backtrace.
This is strongly discouraged as backtraces are fragile.
Please change this test to not include a backtrace. *)
Raised by primitive operation at Ppx_expect_test__Bad_test.get_a_trace.loop in file "bad_test.ml", line 12, characters 17-29
|}]
;;
|
